The chronOS Strip is a synthetic bone void filler manufactured from chronOS beta-tricalcium phosphate (β-TCP) granules and a resorbable polymer [poly(lactide co-ε-caprolactone)]. The chronOS Strip, combined with autogenous bone and/or bone marrow or autograft, is intended to be used in the spine for posterolateral fusion.

The purpose of this prospective, multi-center clinical case series was to evaluate posterolateral fusion rates in a prospective series of patients with degenerative disc disease. The surgical procedure consisted of instrumented posterolateral fusion with interbody support. The chronOS Strip, combined with bone marrow aspirate and local bone, was applied to the posterolateral gutters.

The primary outcome for posterolateral fusion status was a composite endpoint incorporating posterior bridging bone status, intersegmental motion (angular and translational motion) and posterior hardware status. To have successful posterolateral fusion, a subject had to be successful in all four components at all levels under investigation. Failure to meet any one of the four components indicated failed posterolateral fusion status.

The Oswestry Low Back Pain Disability Questionnaire was self-administered to each subject preoperatively and at each clinical follow up examination. Each of the ten questions had six ordered responses coded on a scale from zero to five. The scale ranges from 0-100. A higher score indicates a higher level of disability, and a negative percent change (post surgery minus baseline) indicates improved function.

The Oswestry Low Back Pain Disability Questionnaire was self-administered to each subject preoperatively and at each clinical follow up examination. Each of the ten questions had six ordered responses coded on a scale from zero to five. The scale ranges from 0-100. A higher score indicates a higher level of disability, and a negative percent change (post surgery minus baseline) indicates improved function. Percent change in ODI score was calculated as: [(Month 24-Baseline)/Baseline]*100%.

The subjects completed questionnaires assessing the intensity of pain experienced in the back at the preoperative visit and at all visits postoperatively. Pain intensity was rated on a scale where zero indicated no pain, and 100 represented the worst possible pain.

The subjects completed questionnaires assessing the intensity of pain experienced in the back at the preoperative visit and at all visits postoperatively. Pain intensity was rated on a scale where zero indicated no pain, and 100 represented the worst possible pain. A negative change (post surgery minus baseline) indicated an improvement. Percent change was calculated as: [(Month 24-Baseline)/Baseline]*100%.

The subjects completed questionnaires assessing the intensity of pain experienced in the leg at the preoperative visit and at all visits postoperatively. Pain intensity was rated on a scale where zero indicated no pain, and 100 represented the worst possible pain.

The subjects completed questionnaires assessing the intensity of pain experienced in the leg at the preoperative visit and at all visits postoperatively. Pain intensity was rated on a scale where zero indicated no pain, and 100 represented the worst possible pain. A negative change (post surgery minus baseline) indicated an improvement. Percent change was calculated as: [(Month 24-Baseline)/Baseline]*100%.

The SF-12v2, comprising 12 questions related to health and wellbeing over the prior four weeks, was administered to subjects preoperatively and at all follow up visits. SF-12v2 represents overall subjective health status by measuring eight health-related parameters (each scored from 0 [poor health] to 100 [better health]): body pain, general mental health, perception of general health, physical functioning, role limitations caused by mental condition, role limitations caused by a physical condition, social functioning, and vitality. First, the eight scales were standardized using means and standard deviations (SD) for the general US population. Second, PCS was scored by aggregating the eight scales using a standardized algorithm. Finally, PCS was standardized using a linear t-score transformation to have a mean of 50 and a SD of 10 in the general US population (expected range: 13-69).

The SF-12v2, comprising 12 questions related to health and wellbeing over the prior four weeks, was administered to subjects preoperatively and at all follow up visits. SF-12v2 represents overall subjective health status by measuring eight health-related parameters (each scored from 0 [poor health] to 100 [better health]): body pain, general mental health, perception of general health, physical functioning, role limitations caused by mental condition, role limitations caused by a physical condition, social functioning, and vitality. First, the eight scales were standardized using means and standard deviations (SD) for the general US population. Second, PCS was scored by aggregating the eight scales using a standardized algorithm. Finally, PCS was standardized using a linear t-score transformation to have a mean of 50 and a SD of 10 in the general US population (expected range: 13-69). Percent change was calculated as [(Month 24 - Baseline)/Baseline]*100%.

The SF-12v2, comprising 12 questions related to health and wellbeing over the prior four weeks, was administered to subjects preoperatively and at all follow up visits. SF-12v2 represents overall subjective health status by measuring eight health-related parameters (each scored from 0 [poor health] to 100 [better health]): body pain, general mental health, perception of general health, physical functioning, role limitations caused by mental condition, role limitations caused by a physical condition, social functioning, and vitality. First, the eight scales were standardized using means and standard deviations (SD) for the general US population. Second, MCS was scored by aggregating the eight scales using a standardized algorithm. Finally, MCS was standardized using a linear t-score transformation to have a mean of 50 and a SD of 10 in the general US population (expected range: 10-70).

The SF-12v2, comprising 12 questions related to health and wellbeing over the prior four weeks, was administered to subjects preoperatively and at all follow up visits. SF-12v2 represents overall subjective health status by measuring eight health-related parameters (each scored from 0 [poor health] to 100 [better health]): body pain, general mental health, perception of general health, physical functioning, role limitations caused by mental condition, role limitations caused by a physical condition, social functioning, and vitality. First, the eight scales were standardized using means and standard deviations (SD) for the general US population. Second, MCS was scored by aggregating the eight scales using a standardized algorithm. Finally, MCS was standardized using a linear t-score transformation to have a mean of 50 and a SD of 10 in the general US population (expected range: 10-70). Percent change was calculated as [(Month 24 - Baseline)/Baseline]*100%.

This is a single arm, outcome study for treatment of patients with degenerative disc disease (DDD), with or without stenosis, with interbody fusion, posterolateral pedicle screw system, and the study device (chronOS Strip).

Device: chronOS Strip

chronOS strip combined with bone marrow aspirate plus local bone

Other Name: beta-tricalcium phosphate

Eligibility

Ages Eligible for Study:

18 Years and older (Adult, Senior)

Genders Eligible for Study:

Both

Accepts Healthy Volunteers:

No

Criteria

Inclusion Criteria:

Has the following indication for posterolateral fusion (transverse process and facet fusion) with posterior rod and screw fixation:

• Degenerative Disc Disease (DDD), with or without stenosis. Diagnosis of DDD requires back and/or leg (radicular) pain along with:

Instability (≥ 3 mm translation or ≥ 5° angulation); or

MRI confirmation of Modic Type 1 or Type 2 changes; or

High intensity zones in the disc space.

Has one or two motion segment(s) to be fused between L2 and S1;

Skeletally mature adult, at least 18 years of age at the time of surgery;

Has had a previous interbody fusion or posterolateral fusion attempt at any level of the lumbar spine;

Active systemic or local infection;

Known or documented history of communicable disease, including AIDS and HIV;

Active Hepatitis (receiving medical treatment within two years);

Active rheumatoid arthritis, non-controlled diabetes mellitus, or any other medical condition(s) that would represent a significant increase in surgical risk or interfere with normal healing;

Immunologically suppressed, or has received systemic steroids, excluding nasal steroids, at any dose daily for > 1 month within last 12 months;

Known history of Paget's disease, osteomalacia, or any other metabolic bone disease;

Osteopenia or Osteoporosis: A screening questionnaire for osteoporosis, SCORE (Simple Calculated Osteoporosis Risk Estimation), will be used to screen patients who require a dual energy x-ray absorptiometry (DXA) bone mineral density measurement. If DXA is required, exclusion will be defined as a DXA bone density measured T score less than or equal to -1.0.

Active malignancy. A patient with a history of any invasive malignancy (except non-melanoma skin cancer), unless treated with curative intent and there has been no clinical signs or symptoms of the malignancy for more than 5 years;

Current or recent history (within last 2 years) of substance abuse (e.g., recreational drugs, narcotics, or alcohol);

Pregnant or planning to become pregnant during study period;

Involved in study of another investigational product that may affect outcome;

History of psychosocial disorders that could prevent accurate completion of self reporting assessment scales;

Patients who are incarcerated.

Contacts and Locations

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00943384

Locations

United States, Alabama

University of Alabama at Birmingham

Birmingham, Alabama, United States, 35294

United States, Connecticut

Hartford Hospital

Hartford, Connecticut, United States, 06102

United States, Florida

Bay Area Neurosurgery

Brandon, Florida, United States, 33511

United States, Georgia

Atlanta Neurosurgical Associates

Decatur, Georgia, United States, 30033

United States, Illinois

Northwestern University

Chicago, Illinois, United States, 60611

United States, Kansas

University of Kansas Medical Center

Kansas City, Kansas, United States, 66160

United States, Massachusetts

The Boston Spine Group

Newton, Massachusetts, United States, 02458

United States, New York

Southern New York Neurosurgical Group

Johnson City, New York, United States, 13790

United States, Pennsylvania

The Rothman Institute

Philadelphia, Pennsylvania, United States, 19020

University of Pennsylvania

Philadelphia, Pennsylvania, United States, 19107

UPMC Presbyterian Dept. of Neurosurgery

Pittsburgh, Pennsylvania, United States, 15213

United States, Tennessee

Vanderbilt University Medical Center Department of Neurosurgery/Spine Research